Syphilis is a bacterial infection that's usually caught by having sex with someone who's infected.

It's important to get tested and treated as soon as possible if you think you might have syphilis, as it can cause serious problems if it's left untreated.

It can usually be cured with a short course of antibiotics.

You can catch syphilis more than once, even if you've been treated for it before.

This page covers:

Symptoms of syphilis

What to do if you think you have syphilis

Treatments for syphilis

How syphilis is spread

Preventing syphilis

Syphilis in pregnancy

Symptoms of syphilis

The symptoms of syphilis aren't always obvious and may eventually disappear, but you'll usually remain infected unless you get treated.

Some people with syphilis have no symptoms.

Symptoms can include:

  • small, painless sores or ulcers that typically appear on the penis, vagina, or around the anus, but can occur in other places such as the mouth 
  • a blotchy red rash that often affects the palms of the hands or soles of the feet
  • small skin growths (similar to genital warts) that may develop on the vulva in women or around the anus in both men and women
  • white patches in the mouth
  • tiredness, headaches, joint pains, a high temperature (fever), and swollen glands in your neck, groin or armpits

If it's left untreated for years, syphilis can spread to the brain or other parts of the body and cause serious, long-term problems.

Read more about the symptoms of syphilis.

What to do if you think you have syphilis

You should get tested as soon as possible if you're worried you could have syphilis, because:

  • syphilis won't normally go away on its own
  • getting tested is the only way to find out if you have it
  • the medicines used to treat syphilis are only available on prescription – you can't buy them yourself
  • treatment can help reduce the risk of spreading the infection to others and of serious problems developing later on

The best place to get tested is your nearest genitourinary medicine (GUM) clinic or sexual health clinic.

The test for syphilis usually involves a blood test and removing a sample of fluid from any sores using a swab (similar to a cotton bud).

Read more about testing for syphilis.

Treatments for syphilis

Syphilis is usually treated with either:

  • an injection of antibiotics into your buttocks – most people will only need one dose, although three injections given at weekly intervals may be recommended if you've had syphilis for a long time
  • a course of antibiotics tablets if you can't have the injection – this will usually last two or four weeks, depending on how long you've had syphilis 

You should avoid any kind of sexual activity or close sexual contact with another person until at least two weeks after your treatment finishes.

Read more about treating syphilis.

How syphilis is spread

Syphilis is mainly spread through close contact with an infected sore.

This usually happens during vaginal, anal or oral sex, or by sharing sex toys with someone who's infected. Anyone who's sexually active is potentially at risk.

Pregnant women with syphilis can also pass the infection to their unborn baby. Read more about Syphilis in pregnancy below.

It may be possible to catch syphilis if you're an injecting drug user and you share needles with somebody who's infected, or through blood transfusions (this is very rare in the UK as all blood donations are tested for syphilis).

Syphilis can't be spread by using the same toilet, clothing, cutlery or bathroom as an infected person.

Preventing syphilis

Syphilis can't always be prevented, but if you're sexually active you can reduce your risk by practising safer sex:

  • use a male condom or female condom during vaginal, oral and anal sex
  • use a dental dam (a square of plastic) during oral sex
  • avoid sharing sex toys – if you do share them, wash them and cover them with a condom before each use

These measures can also reduce your risk of catching other sexually transmitted infections (STIs).

If you're an injecting drug user, don't use other people's needles or share your needles with others.

Syphilis in pregnancy

If a woman becomes infected while she's pregnant, or becomes pregnant when she already has syphilis, it can be very dangerous for her baby if not treated.

Infection in pregnancy can cause miscarriagestillbirth or a serious infection in the baby (congenital syphilis).

Screening for syphilis during pregnancy is offered to all pregnant women so the infection can be detected and treated before it causes any serious problems.

Page last reviewed: 23/03/2016

Next review due: 23/03/2018